"Coding issue" responsible for delay in results of Iowa Democratic caucuses, says official

A "coding issue" in a mobile app used to collect data for Democratic caucuses in the U.S. state of Iowa Monday night was responsible for a delayed announcement of results, Iowa Democratic Party (IDP) Chair Troy Price said on Tuesday.

"While the app was recording data accurately, it was reporting out only partial data," Price said in a statement. "We have determined that this was due to a coding issue in the reporting system."

Price said precinct level results are still being reported to the IDP and that they plan to release results "as soon as possible" on Tuesday.

Iowa, a state in the Midwestern United States, held Democratic and Republican caucuses Monday night, kicking off the 2020 presidential primary.

The caucuses brought tens of thousands of Iowa's registered voters to churches, public libraries, and school gyms for discussions of their presidential preferences.

Sitting President Donald Trump won the Republican caucuses, in which participants cast a vote to indicate their support, in a largely symbolic vote as he was facing no significant challenge.

In a string of tweets Tuesday morning, Trump went after Democrats over the episode, accusing them of messing it up in Iowa.

Currently, there are 11 Democrats seeking the party's presidential nomination.

Former U.S. Vice President Joe Biden, Senators Bernie Sanders, Elizabeth Warren, and Amy Klobuchar, and Indiana's former South Bend Mayor Pete Buttigieg, addressed supporters late Monday night despite the delay of the caucus results.

Biden's campaign, in addition, raised concerns "regarding the considerable flaws" in the Iowa caucus reporting system.

"We believe that the campaigns deserve full explanation and relevant information regarding the methods of quality control you are employing, and an opportunity to respond, before any official results are released," Biden's general counsel wrote in a letter to the IDP.